* Sync translations with code
* Sync translations with Transifex
* Remove Mac menu title that isn't displayed and shouldn't be translated
* Add context to logging level strings in GTK client
* Use "µTP" consistently in code
* Use ellipsis instead of three docs in Qt client strings
* Close HTML tags in blocklist-related strings
* Remove trailing space from a translatable string in Qt client
* Add missing plural forms for English strings in Qt client
* Fix spelling: metaInfo -> metainfo
This has a couple of benefits: 1) it is clearly visible to the user that
the list is filtered (doesn't display all the torrents) even when filter
bar is hidden, 2) doesn't lead to filter bar controls being shifted to
the left/right as when "Show:" label text changes.
Split FileTree.{h,cc} and FilterBar.{h,cc} files so that each class
is in its own file.
This breaks translations (some classes got renamed => context changed),
to be fixed by next commit (along with Tx sync).